SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd23539b42f6e681924907c588f9e5bce071c191d07283e2f7b667072d0ee8a1e' 
  AND token = 'u1J9VPF6LmW8jYBuk++Vp1MKIvPZLG3EY+t7vFBmf+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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