SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25a4df23314c9df7f49c160985d8f6530ec1529445667b4472d4e74413e55986' 
  AND token = 'ZvkbbC6ksUq+FuCgi6Ivg3nNdwf+/Y++jzTEpg3acGE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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