SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '57a89c4b2d57e9f5b05fec31db238aca6891b7291092e977c08ac33ede651852' 
  AND token = 'YZapSHKcLKBLjkfQRLm7hIDJqgfiWQFtTI1IMYKTq80=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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