SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54a746d3da730ea267e4a9987e9e383d0cf9d11772fb6ea1237bebf347801bab' 
  AND token = 'bFMnn7munwKZ1Wk+HfEdE4TKErAW2CgN1/CV16RA37I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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