SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '29af6c3c2e6e87e9271c7e98b67f7ee3551ee2796b5b63c1ed6c4f2ed911014f' 
  AND token = 'rK3pYKeiJz85KoRygNzdZKmRWKuq1UVAGnAh/GUY4SQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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