SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72722eea81d6bdf4ffd7f3099f6cf0add8065e472caa6e5ebbfd04a6db744440' 
  AND token = 'lkmfPtBU4wDthMgujLrjDiWoGRjE9mGo7ZJ82jktevY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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