SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6059934bb28244e2e9a8fe69730d8c793656f80a4078e7c52db9b27c64e8b1db' 
  AND token = '7RINbGh/7RYcJOGwt3ZqbmCgx/aVLmnB0L8gwZlbQc0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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