SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'aaa925479aa1464884bfa621455c3b09b28e2bfe26f32541a66c2926f08d1d6e' 
  AND token = 'CHIyNYmAZVVOJZdlRqbKK1PDm+XjRZITBm3cidL42yI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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