SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd5f1a1e0952b544edb4d3f5699bf75843004582bd5238d996906cb114cd8e85' 
  AND token = 'fOUigMSgEBIZ+CbTijAQpbbKtqSG7bbdmjb0nukKLSE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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