SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85804a3afcd7de6f30b06c450e43b66c9d4dab42cace408456a3995b5ac1ad4b' 
  AND token = 'b0oxl09qW/6/IkLoAuaHDWVgI4u2HK4sjt7+Da0Yh6A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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