SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aaf844daa88fa41c919768fa44eedaac1b4c916e8ed181bce5000fced1fb7a97' 
  AND token = 'C391e8iFjV7Bp+LFaM13cQJGjRUE4cUrv26Jf3OZgGc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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