SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5cbd344c431a2d13da94319b69a4e09a444ce45c358461609e2ff1a1ccedc0e' 
  AND token = 'W9zCtQBoaUEA+JMlTXEvwwkWmU6enHAZazMxyl+D/4A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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