SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ade107ab0f83665c61276aebccb6094b7abd717331ec050ac03795ac54b1e548' 
  AND token = 'uDfrnpMEmBgy1ZuSuYsICacL4d9oi/XxXzf+rMKF9NQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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