SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b287a7650ebdc0bd709648ae1a05e61fe29b83a0154997a64519610148f8f116' 
  AND token = 'pys0VTxLj6PndB858LmHXc+gjrUg/ag/apb0Mj5jXcw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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