SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '490ee6214a4f2a4a8f696d0a5600753639189d111ac023cc603659d0e24977a8' 
  AND token = 'mA3doSLRnk2Jm0lAbDo2GbSc5Cs/qWV9POnceX2B+uY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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