SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52446b067bacbbbcf7b29214a674ef8a249d684db7d2ea6a44bbb22a2fd751b1' 
  AND token = 'CWO/V/7R7aprDAJRW9oajyR0tRKqno1mNNcs3F/b4gU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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