SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '434505391544d20d66fb15bf70150b311fba2a128964f78fa1cfa9487fb8ddc5' 
  AND token = 'a3OS9+MIS2G1Rtc/jXnqY+sFqEnC8De6REhsEPtZfsU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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