SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e08dd9459620228f4af3ed8abfbf569aa3708af24e4adabbe4714c412c91727b' 
  AND token = '5IGzeFltte2Wl7+fht+ihX3sev0jccpxzzSgPpxaNrk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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