SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e7d5f57e91ee4d50c86fabcc12770680c862ad2999ec68bc4a90b3f0f0f5f53' 
  AND token = 'cafyFLSM8zeOqql2QkhcpbYhb01jvANTzevez+JZH8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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