SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed60ac7b09f8e645ec16d2ad1b4ef00125eeea6cfd00c75772e184b7d6bfe092' 
  AND token = 'Vr7YCXUtUkksoDs8b4lgiUJ4yCl9xSHEeQo0tDRQhFc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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