SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff82737f6ffd6468a50c10315dfb0c8442833b4879623cdc292c280d05377617' 
  AND token = 'JByNLvbmPZyUjbXhAav0Q1gyFp2/tbGbGPbg04aRYQE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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