SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba6b5cf69b6834e3dac9142b0eeea876e2fc2aa3e111ffa8635176fc7de35eb3' 
  AND token = 'yudjTl/7D31wokqohlpT4nHClkJef7lWJILa5dlVym4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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