SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5898d839f09174e46de44fa2f55161c0444586d3e277cf1ed77a9c64e09bf0a8' 
  AND token = 'RccwiIOsgycSDGSuoXA0mV8ipT+zIwsLPjVefTwLdfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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