SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0784ddd3e45de9b639cc6fa706f1d668ff215eb2481523579446f9598d1ba8dd' 
  AND token = 'ulifcypxtdAFRVD5Bn/xEpVcFukfpCX5vp0tZdUx2Tw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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