SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '37881f9022c0d90644bff5b56ee1eac4858572c3812c0829aee722013268991c' 
  AND token = 'xcE0JquPSHrh7FhYGNqdwUPRjWefvHaipDdzE/6XTpE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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