SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d205caee5642ffcbaff52f48cc4fae3be15909ec99283f8849f7b3e0060cbe8' 
  AND token = 'W72O+MajjoVdFEL4psw2Yitgomc5cZJIsLJ/G2YJWy4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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