SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ad85fbcc627b66a1430c1fe4aef0c5a5d904b861d0547f38193f951db49047a' 
  AND token = 'V2Cb2+SMrQuiroxRA0RUAIKfapq6DSeTCWFvZchINJw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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