SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '089d87da1233dceed30830362aca549cc99da350fe7a94169f42613d0338323a' 
  AND token = 'MJfJv/wo/h8Cu1UsX+p75XXZhZZ6HnVa+JjgC2SqWIg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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