SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4d9acd348653c67fa1203209874e371e813f3984e3f5386588c592710156f159' 
  AND token = 'M240MrToV+bsWXtXPaHv02OJ80RyHy03x772kwnFAGg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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