SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '977af6e251bc96142ed026509c934edd151f2ed7c40f42ad89acc641c1f7c4b3' 
  AND token = 'FXyWYUax4SQw8UjG2qyQ2PqnPk9bwr5jilCJR2YGsDA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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