SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70e650c16b7d88064a2a603a47c8f42f8270ffc6e420ea3f6f9872f515053d68' 
  AND token = 'e5sa/BgbmsqtYgLRCzHrfBMmjPI6WzmhxJWvCQquqWw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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