SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac276812429d9c0cf3e34cb299eb25a9f5833eb5531fde37470c267e8bd686ef' 
  AND token = 'P6dz1Fx3MalJJBmnLrMuLAXChPBC7DwwVz3+eIab1KE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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