SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '537e16d2ed45e2030e3c8523eec673f773f70b9b72655d3163fb95aac60ca887' 
  AND token = 'Vb2AXYYxVNAWZnCbAfG1E4KwW0iVhsaq+UK1zzZZG4k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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