SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45718e0101f75485c2af5420149f19507a5b9d0dc4bccdd0486ebbdd8a00d473' 
  AND token = '5QapLOjH3lgFlUAnT3QL90rI5qYZHzhWJZ4vhXmVeu4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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