SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0730cdd2b390d9165f086e3ea7a5fbe0e92fc4afe010b70fbbf526f27e579f53' 
  AND token = 'TlGhgHnPVDaYvE/BJSweXhNCl+B0RE1h1jd//kCGbcY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}