SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ae04dd3fb903a5030211efbb89dc481156f2dfac592312159b8a66a26d1679c7' 
  AND token = 'fgdMdmNCr51zOm7Ktxow2ut5sZAVGOXABDP+bLvlgBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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