SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dff84f161c48d5bba76a3d068851545e5e32aa7cf88cdef0bd46ca64dc5b5fcb' 
  AND token = 'ZyEczx7dLSSKyybNriHIwsJhCWApFSgdDksHU2hOfmc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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