SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de5227be836d3ebbb52c9edba61e62f2cf907b2a200a2e92e7f24d31eabfb23c' 
  AND token = 'egqlhe8tAtYuDS4VUwcrwF5tgSvUeaqBEGSXV7PrWB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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