SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '38e34ef5388493bf072c509958f92c1d7a8919acd68a10650b0aa60149a35061' 
  AND token = 'QpLjnjDUjwwLAJVBBlTx/0GgqH8vU2DVL3ry6bg9ow0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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