SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '711d13bf236b5ec5102f18e9f926fff0f4996e7f54d95c930ac5518b05d8599f' 
  AND token = 'M0jKPQ4h+pncy7YkYE9+rV1IvQKwT2ycU1JNvPNg07Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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