SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '79c6a40ec6e09cfb2a1ed18d51051534faa24a76cbf0d4ecb03dde3503980d9a' 
  AND token = 'guckyk/qzg1REjvgjxkifpAVpcac2niGahfrt/r5kcM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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