SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '755ba32db90c1e3f69140857ca314c3e2fa3c0417f5210e7c3cff961fd27e4c5' 
  AND token = 'QwqX6MK9tlj7I06RBpvdGE8XVKf9rtSHzQOBMYaqVAo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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