SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8133bf9693655060e08d1c906f9896bb97695d8c3a18d23a321412741d485090' 
  AND token = 'cuDQdE3tSEKO8Vr+2ZMvpi/G7MsgJgLv/N5BW9GQlP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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