SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4bc7b960577df6724aed56901e39c131285c35ddca473190b07a27a6a2642269' 
  AND token = 'qNTPbM2SksmtSzIB9JJoVsNeAxo+PFFWyEOATFrmmlc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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