SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9673cf08ad553cfd00c16bfee5affbaadc5bdc2d0d2901508db9e04a3c760447' 
  AND token = '1eQyaqmFDup7z8StlvQuPZSADDM+ugfqpTOKn4tZ3CY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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