SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5438e3411e9efefcf7675fc4037692784d5d62e13dd885c01ba4ba47befbfb24' 
  AND token = 'QMctrgofYANLLfsgqH03X09vRKm9dPKFEPe/Oep5DqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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