SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5dfc7c619bee7707d49a2e7880e747a449064f12bc2ba2c57cb75dfecd297cc' 
  AND token = 'Hk68/ml1ae4gxoG/AboUfUTRC73zOAyM5aJOei1Za4s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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