SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '779254f52606fd654bbd9641816d0abbe8824bb14e651d46c2341a6dabe56e4e' 
  AND token = 'APLbi3b2cY6RBaa3n3f7bSMikXEq+VFG0YcshLJjoH4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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