SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70af837e07c82783dc8351d88e4f4d2a262085fa4d20ec42072a3a6fdce3451d' 
  AND token = 'Cupq0keZJSAfKKRj1ente0JX0Q0aYs7jJdp6YSSKkFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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