Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dce6b3c23e8bba49e3e72a34d5a4b5ed03a1590916c60532384ea416976782a5' 
  AND token = 'C5aZ+Vm/Sl4/c1ZsddnUTePIvP9fQXb08dtqxDTFPkQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}