SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a712918430d76a39158cf9dd91f8c66dd428656882ecbc974cce21bd5b036ee0' 
  AND token = 'Ga3jRaAGDa/KuJ4pPxvq4Rw4erYK+CGGKLfBm2UYENA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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