SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '354ecabc0e0398ca45e5923c0b08456f289b1ac542b12061e22cc3614f44c848' 
  AND token = 'eNjGoFdpHDMZRLQ3WEfwjTyHy7AX1Db+1k9h/JwH+cE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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