SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7f720828818f6d6350c52f7fafaf3120abd31a060123e2c31f6b7a523052b8dd' 
  AND token = '5czWynz+x6zh8TflQpM8ZjmRYQaLFN/ZVsl7Bv6Kk/4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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