SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '877213bdaedce8af7050652fb62356226abd525253158c63a1c62a877f78ac3e' 
  AND token = 'CCRufmlyYYyOgg7FUFKkuir2r/qM6hX6tsTd3GB2wXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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