SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'abfe4ff19464bf8177024d1515e987f503f840568bfe7cdac09074704ce4379e' 
  AND token = 'ib/nBWw2GQDuIty+prDhftjuFSPV+GeNiv6islXmqOU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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