SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e509078f2ac21c8d6e7b93b9b275a2f9366714c076c0c1f5ba6b797ff4d1817' 
  AND token = 'NVTsSIqexS6L8ytKhh/xXL4eH4rHPviGbu/G+gGDmTQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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