Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27c19ab1cf6869dc9350927338e3b0627c2688cfdc4e816156161e5fb9e2f420' 
  AND token = '0kJuTR+VQiUuUeMMwosjms9C0FpbM409AnL87t8/KjI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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