SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd9e1c4ab6571de182b8d5d31ac6122fd73ab5203f112457331beed79a4756c7e' 
  AND token = 'n14olJtnxv/B8FaP1/3hxEVp/Mf9DFvNBwPjS+SdaBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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