SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5abfc2116684a5f13f059f94724bf11e8416429348f5b027247e2f592cb54d26' 
  AND token = 'qjO8ACeyQl1swDZmmTrme4znlQyDqfU0P01NpEpUFZ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}