SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8e567411a5baa8d53cea6d0a902c4bf679476441a17a7b5c7d3818aba25d26b' 
  AND token = 'VgSLY4qxbNsMyvLeNv04jUAHuB+Fy4rByXRMw1wUlqA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}