SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e200329aac3644a35e0e4c4340274cd8670c2090a7e1ddd7ece4baa92b17d0b' 
  AND token = 'rWljGDJDe4tE4gkxjtzucw7W2ucsfBUU3ge/CXkO3mI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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