SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4434707bdbd2d0ddfb04cb897cd6df0983581efdd74e419bccb38c95e24fdf2' 
  AND token = '4PENEXU9hmjjInrS1slU9nHc2FicOA17JYGnDau8iuM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00065

JSON explain

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