SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65935316e38e5d3ea39f587246b05abfcab5295a2ce437a6ed649f88641ef201' 
  AND token = 'kJxyIDhF+f99RxRwHwlTonMU+Zo9IoGTJIJbl2R9Bm0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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