SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cea6aca5b7bb5abe51aa378bcb42afd506cb865dcfc5e117cb2824c59671c211' 
  AND token = 'im9ci9BYie99eIfSHzhVhEKdW8rCcjevSBHFuO05Zfk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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