SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4963fc70f12639e67c27b9115be8317db09dd6f86032b1744a7184fbdccd91a0' 
  AND token = 'gF7OFOtffTD7ALgY7YHnWgFLTySJjIYc0vELFHDBbFA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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