SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1918ed76c5f2a527c54a40a496a7c5961be095a4b7fa1d3ff4e287c2b3931df7' 
  AND token = 'FEwWk/U5SvfxZYd937Gfc3FbNHET5Gpj6JIQ2KIAzjM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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