SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1c67e42fba21a8ad8dcba882f7da50059c8817b127752b8940bfcf1a75389da5' 
  AND token = 'UiFEX5jMAUphjlwwqj+JYmcnjwyAGT1Skm9GgubCzt0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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