SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8813349209a3036a2900510c996fbda289521c03ff551bc1f7fe184c8ab1160d' 
  AND token = 'OIuPlYHGUUeBbLocox6wbE9Qq72sDbsUZgCNjyIuZdo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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