SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce2d583ddc1282a0529271e0913dbd1fd5aef4156d6c5dfc8306524e3edae753' 
  AND token = 'pg7jFwYkrIkW/Ae5Vp1Y6WIrB8ul+GQfdK0ZG6SYEm0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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