SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1bf803786bbab3d3f82fc5f1b4644e8d8c7a1966a67835e598d24e61059f861e' 
  AND token = 'WV2D5CwL8fIbTn1WAh7w1yBDFQexbIU5c+dA0I3GCUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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