SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9b8721dde9f24148593e2cbe4f050d6f3368f023ce15a0e714f411ce9daae1d' 
  AND token = 'wLBkQyvBqfPx7Cspw6FYNfqHUCk6kYBCdcOohszTfYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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